Electric switch



July 13,1926.

- c. L. HOPKINS ELECTRIC SWITCH Filed on. 18, 1919 4 Sheets-Sheet '1July 13 1926. 1,592,526

0. L HOPKINS ELECTRIC SWITCH Filed Oct. 18, 191 9 4 Sheets-Sheet 2fiver/for.-

' C. L. HOPKINS ELECTRIC SWITCH Filed Oct. 18, 1919 4 Sheets-Sheet 5July 13 1926.

1,592,526 C. L. HOPKINS ELECTRIC SWITCH Filed Oct. 18, 9 4 Sheets-Sheet"4 2 M QWW v WI-@ 6.

Patented July 13,

UNITED STATES PATENT OFFICE.

CHARLES L. HOPKINS, or RIVER FOREST, ILLINOIS, Assreivon'ro Banner/HumanH TRIO MANUFACTURING ILLINOIS.

COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION,OF

LECT IC SWITCH.

Application filed October 18, 1919. Serial No. 331,624.

breaks are made in the circuit substantiallysimultaneously,therebydividing and decreasin the arcing effect, and consequently lessening thedanger of injury to the switch, and other undesirable effects.

A further object of my invention is to provide an electric switch foruse in an electrical receptacle, which will be simple in construction,and etlicient 'in use, and

cheap to manufacture. 1

Further objects will appear from the detaileddescription to vfollow andfrom the appended claims.

In the drawings, in which two embodiments of my invention are shown:

Fig. 1 is a plan view of a pull switch 90 socket embodying my invention;

Fig. 2 is a section on the line 22 of Fig. 1; i

Fig. 3 is a section on the line 3-3 of Fig. 2; i

Fig. l'is a section substantially on the line 4l-4 of'Fig. 1;

Fig. 5 is a section substantially on the line 55 of Fig. 2; I V

Fig. (Sis a section substantially onth'e line 6 7 of Fig. 1 looking tothe left;

Fig. 7 is a section substantially on the line 6-71ot Fig. 1 looking tothe right; j

Fig. 8 is a detail perspective view showing part of the switch frame;

Fig. 9 is a detail perspective view" showing a combined bearing andspring retaining member Fig. 10 is a. detail perspective view of:

one of the rotatably mounted switch contacts;

v Fig. 11 is a detail perspective view of of Fig. 12;

Fig. 14 is a section on. the. line 14-1 l of Fig-13; V

Fig. 15is a section substantially on the line 1515 of Fig. 12;

Fig. 16 is a section substantially on the line 16-17 of Fig. 12 lookingto the left;

Fig. 17 is a section substantially on the "ing, repair, etc.

Fig. 13 is a section on theline13-13 line 16117 of Fig. 12 looking tothe right;

Fig. 18 is a detail perspective viewof a fixed spring contact memberforming part of the switch; 7 i i Fig. 19 isa detail perspective viewshowing a combined bearing and spring ,retaining member; and I I Fig. 20is an exploded perspective view of certain'parts of theswitch. i 1

In order to give a general idea of the construction of. Figs. 1-11inclusive, it is here stated-that my invention is here shown embodied ina pull switch socket, having shell and center contacts, 25 and 26respectively, for engagement with an insertable 'de 1 vice of the Edisontype and having wiring terminals 27 and 28 for connection with a pair offeed wires, (one of the wiring terminals 27jbeing connected directlywith the threaded shell contact of the receptacle) and a pull switchmechanism having. two rotatably mounted contacts'29 and 30;(in sulatedfrom each other in the off posi:

tion), one ofthese contacts 30 being electrically connected with thecenter contact, and the other contact 29 being electrically connectedwith the other wiring terminal 28, and a relatively stationaryelectrical conducting member '30 with which the two rotatable contacts29 and 30 both inakecontact in their movement, and with'respect to whichboth of said contactsare movable out w of contact intlieir movement,whereby as ously. I p

The receptacle contacts, switch mechanism and Wiring terminals are allmounted on an insulating base 31. and this insulating base and partscarried thereby are housed in a sheet' metalcasing 32 having-a sheetmetal'ca'p 33, whichcan be removed for. wirthe contacts are rotated, thecircuit from the 'w1r1ng terminal to the center contact 15 brolc en attwo points, substant ally snnultane The usual lining .34. of

above the insulating base 31 to prevent short cir'cuiting of the liveparts carried by the insulating base.

v The wiring terminal 27 is electrically connected with the threadedshell contact 25 by means of a screw '36 (Figs. 1 and 3) the head ofwhich engages the flange 87 of the threaded shell contact, and the upperend of which is threaded into the wiring terminal 27 The wiring terminal28 is secured on the insulating base 31 by means of a screw 37 (Figs. 1and The wiring terminals 27 and 28 are provided with the usual bindingscrews 38.

The pull switch mechanism comprises (in addition to the two separatedrotatably mounted contacts 29 and the connecting member 30, previouslyreferred to), a rotatably mounted insulating contact-carrier 39 to whichthe contacts 29 are secured, (the contact-carrier, together with thecontacts carried thereby forming a commutator memher), an oscillatableoperating member or switch-lever -10, which is operated to impartmovement-to the co mnutator, ratchet mechanism 41 between theoscillatable lever 40 and the commutator for changing the oscillatingmovement of the switch lever 40 to av step by step. movement in thecommutator, a pull chain 42 carried by a chain-rail 43 for operating theswitch lever 40, and a coil tor sion spring a l for returning the switchlever 40, after it has been operated by the pullcliain A shaft i5 issecured to the contact-carrier 39. This shaft may be molded into, thecontact-carrier if desired. One end of this shaft is rotatably mountedin a combined bearing and spring retaining member to which is adjustablysecured in an opening l7 in a bracket d8. This bracket 4-8 is secured inplace on the insulating base 31 by means of a screw 418, which screwalso serves, to electrically connect this bracket 18 with the centercontact 26. The contact 30 is electrio-ally connected with the shaft;(4:5 by means of an arm or connecting member 5,0, which e:-:tendsinwardly from the contact, and surrounds the shaft i c, this shaft 4 43,being of conducting material, so that the contact 30 is alwayselectrically connected with the center contact 26 through the screw 49,the bracket as, the shaft all), and the arm 50.

This arm 50 is also provided with ratchet teeth 51 which form part ofthe ratchet mechanism -11 between the switch leverl0. and thecommutator, the switch lever 40 being provided with depressions 52 forcooperating with the ratchet teeth These. depressions 52' have slopingbottoms, which slope down from the surface of the lever 40, terminatingagainst the shoulders 53, against which the free ends ot the ratchetmembers 51 engage when the switch lever 40 is rotated. These depressions52 may be formed in the lever 10 in the operation of stamping, the lever40 being made from sheet fibre, which is of such a nature that thesedepressions can be formed by stamping. The chain-rail i3 may be a sheetmetal stamping, having a curved arcuate portion 54- in which the chainlies, and having a hook portion 55 for engagement with one of the ballsof the chain 42, whereby the chain is secured to the chain-rail. Thechain-rail is secured to the switch lever 0 by means of integralprojections 57 (Figs. 2 and T) which extend through openings in thelever 40, the ends of these lugs being bent over to firmly secure thechain-rail in place.

One end of the torsion spring ell is secured to the switch lever it) asshown in Figs. 2 and l, the end of the spring engaging a lug 58, and theother end oil the spring is secured to a lug 59 (Figs. l and 9) formedintegral with this bearing and spring securing member 4-6. Foradjustably securing this bearing and spring member in the bracket 48,tor adjusting the tension of the torsion spring i i, the member isprovided with a struck-up portion, or lug (50 (Figs. 2 and whichstruck-up portion can be made to engage in any one or three slots 61,extending outwardly from the opening i7 in the bracket l-S. (Fig. 8),the member 46 is provided with a slot 61 for engagement with ascrew-driver, whereby the member L6 can be pushed inwardly and turned tothe desired position, and then allowed to spring out again, (under theaction of the spring a l) to cause the lug ($0 to again engage one ofthe slots (31. As previously stated, the purpose of this torsion springll is the return to. switch lever l0 after it has been operated by hepull chain 4L2. It also exerts endwise pressure to keep the ratchetmembers in engagement. Pulling down on the chain 42 revolves thecommutator through the ratchet mechanism 41. After the chain has beenpulled down, it is released, and the torsion spring l i returns theswitch lever 40 and pull chain 42 to their original positions, thecommutator, however, remaining stationary during this return movement,the ratchet mechanism all permitting this return movement of the switchlever elO without a corresponding movement of the commutator, 1 it Thebinding terminal 28 has a bracket portion 62 formed integral therewith,which has an opening which provides a bearing for one end of thecommutator. The contact 29 is electrically connected with this bracketportion (32 by means of an arm (33 (Figs. 5 and 10) extending inwardlyfrom the contact, this arm 63 being provided with a sleeve portion 6%which tits snugly in an opening in the bracket portion (32, and in whichsleeve Get an extension 65 of the contactcarrier 39 fits snugly (Figs. 2and 5). The contact 29 is thus always in electrical connection with thewiring terminal 28 thru the arm 63, sleeve portion 64 and bracketportion 62.

As previously described, the other rotatable contact 30 is always inelectrical conrier.

. as will move the commutator degrees of movement.

nection with the center contact. In the off position o1 the switch,these two ro-' tary contacts 29 and 30 are insulated from each other,but in the on position of the switch they are electricallyconnected witheach other through the connecting member 30. The circuit from the wiringterminal 28 to the center contact isthus made and broken at two, pointssimultaneously by mov- 30 can be moved into'and out of engagementtherewith, by rotating the commutator. The contact carrier 39 'isprovided with a centralflange p'ortion70, which forms an insulatingbarrier and serves to prevent short circuiting or arcing between the contacts 29 and 30. "Each of the contacts 29 and 30 is spirally curved toconform to a corresponding spiral portion ofthe contact carrier, thecontact being provided. with an inturned projection 72 (Fig. 6) whichserves to position the contact onthe contact car- It will be observedthat in this form of my switch mechanismthe insulating contact carriercomprises a pair of cam wheels having spiral cams, and a circular flangeextending above the camsand forming an insulating barrier between thecontacts can.

ried by the cam wheels.

The switch operating mechanism is so constructed that each'pull of thepull chain 7 As shown in Fig. 6 the cam Wheels of the contact carr1er72are each provided w th a spiral cam portion 73 against which thespring contact fingers GS and 68 bear during a. part of the movement ofthe contact carrier. hen the commutator is rotated from the positionshown in Fig. 6 the contact fingers 6S and -3 ride upon the surfaces ofthe spiral cams 73 and finally snapoif from these spiral portions downinto contact with the spirally curved contacts 29 and 30. During theneXt 180'degrees of movement, the spring fingers 68 and '68 ride alongthe spiral contact-s29 and 30 and-finally snap down on" from the ends ofthe spiral contacts onto the spiral insulating portions 73.

The operation of the switch has been outlined in connection with thedescription of the construction.

39 through 180 chain is then released,

When the switch is in on position,

that is when the spring fingers 68 and 68:

are in engagement with the contacts 29 and p '30, the circuit is fromthe wiring terminal 28 throu h the bracket oortion 62, arm

63, contact portion of the contact 29, spring finger 68, base portion66, spring linger 68,

contact portion of the contactBG, arm 50,

shaft 45, bearingmember 46, bracket 48 and screw e9 to the centercontact 26, thence through whatever translating device is inserted inthe receptacle,to the shell contact 25, and throughthe screw 36 to thewiring terminal 27. a l

Assuming that the parts are in positions corresponding to that shown inFig. 6 (in which theswitch is in oii position), the

spring contact fingers 68 and 68 being out of engagement withthecontacts 29 and 30 and resting on the insulating spiral cam portions 73016 the commutator, i'f/it is desired to move the switch to on position,the chain 421is pulled down until the projection 74 engages the shoulder7 5 of the insulating base 31. This moves the lever a0 thru 180 degreesand also moves the commutator thru 180 degrees thru theinten' mediaryofthe ratchet mechanism 4L During this movement of 180 degrees, thespring contact lingers 68 and 68 ride upon the spiral portion and at theend or" the movement snap down simultaneously upon the contacts29 and 30respectively. This simultaneously makes a connection at two points, andcompletes the circuit between the wiring terminal 28 and the center contact. the torsion spring 44; returns the switch lever t0 and pull chain42 to their original position, the commutator however remainingstationary during this return movement of the switch lever t0, theratchet mechanism ll permitting this return movement or movement of thecommutator. The spring The pull chain is then released, and

lingers 68 and 68 would resist a ret'urng movement of the commutator asthe ends of these spring fingers would engage the shoulders at the endoi'the spiral cam por- 1 tions 73, and would prevent a return movementof the contact-carrier.

V The return movement of the switch lever 40 under the actionof thetorsion sprlng it is limited by the engagement of the projection 7-lwiththe shoulder 76 (Fig. 4).

If it is desired to move the switch from ment of 180 degrees, thecormnutator re- During this &

maining stationary during the return of the switch lever. During thisforward movement of 180 degrees of the commutator, the spring contactlingers 68 and (38 ride upon the spiral contact 29 and respectively, andat the end of the movement these 7 spring fingers 68 and 68 snap oilfrom the ends of the spiral contacts, thus making a quick simultaneousdouble break in the circuit from the wiring terminal 28 to the centercontact, thus breaking the are at two points and greatly lessening thechances of injury to the contacts and other undesirable effects.

In the form of my invention shown in Figs. 12 to 90 inclusive the shelland center contacts and 26, the wiring erminals 27 and 28, theelectrical connecting member 30 the insulating has 31, the casing 32,the cap 33, the fibre lining 3 2, the fibre cover 35, the screw 36, thepull chain 4-2, the bracket 18, and the screw 1-9, which secures thisbracket in place and electrically connects it with the center contact,may be the same as in the form previously described, the main featuresof difference being in the switch mechanism itself.

The switch mechanism shown in this form of my invention comprises arotatably mounted connnutator, including a contact 77, (which is alwaysin electrical connection with the wiring terminal s8) a contact 78,(which is always in electrical connection with the center contact 26),and a builtup contact-carrier 79, to which the contacts 77 and 78 aresecured, and comprises also a built-up oscillatable switch operatingmember or lever 80, which as it is oscillated imparts a step by step,movement to the commutator, a ratchet mechanism 81 between the switchlever and the commu tater, and a coil torsion spring 82 for returningthe oscillatable switch lever after it has been operated by the pullchain 42.

Many of the details of the switch mechanism are shown in perspective inan en ploded view in Fig. 20. The built-up switch lever or operatingmember com )rises acentral spider like member 83 (Fig. 20) (having anopening 84 through which the supporting shaft 85 extends) three discs86, 87, and 88, which are slipped over the legs of the spider 83, and aspacer sleeve 89 which separates the discs 87 and 88 and is also slippedover the spider. These discs 86, 87 and 88 are formed of suitableinsulating material, such as sheets of fibre, and the sleeve 89 is alsoformed of insulating material. The spider 83 is also provided withratchet teeth 90 for engagement with cooperating ratchet teeth 91, stuckup from the arm 92 of the contact 7 8. The spider 83 may be a suitablesheet metal stamping, as may also be contacts 77 and 78. The pull chaina2 is secured to the switch lever 80 by means of a hook member 93, (Fig.20) having laterally extending lugs 9 1, which engage openings and 96respectively in the fibre discs 87 and 88.

The legs of the spider are provided with outwardly projecting portionsor lugs 97, to hold the insulating discs 86, 8'7 and 88 and the sleeve89 in position on the spider.

In assembling the switch lever, the legs of the spider are bent inwardlyenough to permit the discs 86 and 87, the sleeve 89 and the disc 88 tobe slipped over the outwardly extending projection 97. The cars 9st ofthe hook member 93 are inserted in the openings 95 and 96 respectivelybefore the discs 87 and 88 are moved up snugly against the ends of thesleeve 89. The discs 86, 87 and 88 are prevented from slipping ofi' atone end by their engagement with the ratchet teeth 90 and are preventedfrom slipping otl' at the other end by their engagement with theoutwardly extending projections 97. In order to position the discs 86,87 and 88 on the spider 83 and prevent relative rotation therebetween,each of these discs is provided with a number of recesses 98 extendingfrom its central opening, these recesses 98 being provided to receivethe legs of the spider, when the parts are in assembled position. Thechain 12 is secured to the hook member 93 by engaging one of the ballsin the hook portions, the shank which connects the balls lying in thespace between the two hook members 99. 'ihc discs 86, 87 and 88 and thesleeve 89 fully insulate the pull chain 42 from the spider 83, (the disc86 serving to cover up the end of the projection 94, which wouldotherwise be exposed). The switch lever 80 is supported at one enddirectly by the shaft (which extends through the opening 8& of thespider), and is supported at its other end by a combined bearing andspring securing member 100 (Figs. 13 and 19) this member 100 having acylindrical portion 101, which fits inside the legs of the spider 83,and extends through the opening in the disc 88, and thus forms a bearingfor the spider and disc.

One end of the coil torsion spring 82 is secured to the spider, asindicated at 102 in Fig. 17, and the other end of this coil torsionspring is secured to the member 100 as indicated at 103 in Fig. 13. Themember 100 is adjustably mounted in the bracket l8 in a manner similarto that in which the member 4:6 is mounted in the form of my inventionpreviously described, the member 100 being provided with a struck-upportion 104, which can be made to engage in any one of the notches inthe bracket 18, the end of the member 100 being provided with a notch105, to receive a screw-driver or other suitable tool. By inserting a,screw-driver in this notch, and pressing the member 100 in- Cir wardly,until the lug 104 is disengaged from the notch in the bracket 48, themember can be turnedin either direction, 'to

tighten or loosenthespring as may be de- Letters Patent is: I

sired, to give it the proper tension, and the screw-driver can then bewithdrawn to permit the lug 104 to engage the, proper notch in thebracket 48.

The built-up contact-carrier comprises two similar ratchet shaped discs106 of insulating material (see Fig. 20). these discs supports thecurved contact 77 and the other supports the curved contact 78. Thiscontact carrier also comprises a sleeve 108 of insulating material,(which is slipped over the shaft 85 and uponwhich the insulating discsare slipped), and a separating disc 109 of insulating material,also'slipped on the sleeve 108, which serves to insulate the contacts 77and 78 from each other. The contact 77 is provided with an integral arm110, extending inwardly, and having an opening through which the shaft85 extends,

this arm 110 serving to assist in holding the contact in place on thecontact-carrier, and

also serving to electrically'connect the contact'with the wiringterminal 28. The insulating sleeve 108 extends through the opening inthe bracket portion 62 of the wiring terminal 28, and thus insulates theshaft 85 from this bracket portion, thus preventing a short circuitbetween the contact 78 and the Wiring terminal 28.

'The contacts are positioned on the discs 106 by means of an inturnedlug 111 which engages a corresponding notch 112 which prevents thecontact from slipping on its support.

The contact 77 is thus always in electrical connection with the wiringterminal 28, through the arm 110 and the bracket portion 62. The contact78 is alwaysin electrical connection with the center contact, throughits arm 92,,shaft 85 or spider 83, member 100, bracket 98 and screw 4L9.

In the off position of the switch, the contacts 77 and 78 are notelectrically connected, being insulated from each other. In moving tothe on position of the switch, however, the spring fingers68 and 68 snapinto engagement with the contacts 77 and 7 8 respectively and establishelectrical connection therebetween. When the switch is moved from on tooff position the spring fingers 68 and 68 snap oft ofthe rear ends ofthe contacts 77 and 78 respectively and thus break the electricalconnection therebetween simultaneously at two points, as in the formpreviously described, thus dividing the arc. I l

The movement of the switch lever 80 is limited to 180 degrees by meansof a projection 113 on the disk 88 which engages the shoulder orabutment 7 5 to limit the movement in one direction, and engages the Oneof ioulder 'Tfi'to limitthe movement in the other direction. j p 'Havingthus described my invention, what I claim new and desire to secure by 1.A switch comprising a base, a movably mounted contact carrier ofinsulating mate.-

rial supported bysaid baseftwo contacts of conducting material mountedon said contact carrier, and insulated -from each other base andarranged to be engaged by both oi? said contacts in their movement, andwith respect to whichboth of saidcontacts also move out of engagement111 their movement,

whereby said contacts are alternately con-- nected and disconnectedelectrically with respect to eachother by means of said bridgingmeans,said bridging means being provided with a pair of contact tongues straddling said barrier. 2

2. A mounted. commutator, having two spiral insulating portions lyingalongside each other, and two spiral conducting portions lying alongsideeach other, said'spiral conducting portions being insulated from eachother in the off position of the switch, and bridging means ofconducting material with which both of said conducting portions makecontact in their movement, and with respect to which both oflsaidinsulatingportions also make contact in their movement, said bridgingmeans being provided with two contact fingers, said fingersbeingarranged to snap o-li said conducting portions on to saidinsulating portions to break the circuit at two points. simultaneouslyand to snap o'li' said insulatingportions on to said conducting portionsto make the circuit at two points simultaneously.

3. The combination of an insulating base, a.-

rotatably mounted insulating member car- -make and breakthe circuitthrough the same and electrically connect and disconnect said bearings.1 v p p 7 4:. A switch socket comprising an insulating base, a wlringterminal and receptacle switch comprising a irotatably ried thereby,ratchet means for rotating said contact supported on saidinsulatingbase, a

rotatably mounted insulatingmember carried thereby, ratchet means forrotating said member. a pair of switch contacts carried by saidinsulating member, bearings for said.

insulating member having electrical connection with said contacts, oneof said bearings being electrically connected to said wiring terminahaml the other of said bearings being electrically connected co saidreceptacle contact, and a stationary bridging member arranged to connectand disconnect said switch contacls, and thereby make and break hecircuit" through the same and elecl'rica ly connect and disconnect saidbearings. 10

in witness whereof, I have hereunto subscribed my name.

CHARLES L. HOPKINS;

